A remote, unauthenticated attacker can issue various JNAP calls by sending specially-crafted HTTP POST requests to http(s)://<router_ip>/JNAP/. Depending on the JNAP action that is called, the attacker may be able to read or modify sensitive information on the router.

It should also be noted that the router exposes multiple ports to the WAN by default. Port 10080 and 52000 both expose the administrative web interface to WAN users. Depending on the model, additional ports may be exposed by default as well.

Impact

A remote, unauthenticated attacker may be able to read or modify sensitive information on the router.

Solution

Apply an Update:

If possible, users are encouraged to update their firmware to the latest version to remediate these vulnerabilities. Linksys has provided the following fix versions: